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arXiv · 1308.6183

Electric-field-induced metal maintained by current of the Mott insulator Ca2RuO4

Fumihiko Nakamura·Mariko Sakaki·Yuya Yamanaka·Sho Tamaru·Takashi Suzuki·Yoshiteru Maeno
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Abstract

Recently, application of electric field (E-field) has received considerable attention as a new method to induce novel quantum phenomena since application of E-field can tune the electronic states directly with obvious scientific and industrial advantages over other turning methods. However, E-field-induced Mott transitions are rare and typically require high E-field and low temperature. Here we report that the multiband Mott insulator Ca2RuO4 shows unique insulator-metal switching induced by applying a dry-battery level voltage at room temperature. The threshold field Eth ~40 V/cm is much weaker than the Mott gap energy. Moreover, the switching is accompanied by a bulk structural transition. Perhaps the most peculiar of the present findings is that the induced metal can be maintained to low temperature by a weak current.

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Fumihiko Nakamura, Mariko Sakaki, Yuya Yamanaka, Sho Tamaru, Takashi Suzuki, Yoshiteru Maeno. 2013-08-31. Electric-field-induced metal maintained by current of the Mott insulator Ca2RuO4. https://arxiv.org/abs/1308.6183

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